Minimizing Ash Coal build up in Catalytic ZC

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Jacklumber

Member
Oct 7, 2017
29
California
I have a FireplaceXtrordinair Apex 42 Catalytic zero clearance fireplace with an ash charcoal build up issue. A wheel barrel full per week! I have read that catalytic stoves need to be run with a full load to burn efficiently while reducing airflow. But this leads to significant coal buildup in my Apex 42. I am now starting another method of using much less wood and racking coals to the front near air intake, adding new wood, maybe 1 or 2 logs at the back. I am also leaving air full on to break down the coals. Cat temperature 550-650F. (850F using old method)

This second method contradicts the full load recommendations I read, so I'm asking what is the best way to run a Cat Stove with minimal unburned coal buildup? Any good techiques anyone?

Should Cat and non Cat stoves be treated in the same way to reduce ash coals?
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,548
South Puget Sound, WA
It will vary with the stove/fireplace design. Maybe next time try to place smaller (2-3" thick) splits on the coalbed and run it wth the air at 50%?

Have you tested the wood for moisture content with a probe inserted on the freshly exposed face of wood after resplitting?
 

Hogwildz

Minister of Fire
Seems to me, pulling all the coals forward and laying splits in the back, are not giving the splits anything to ignite or burn from. I tried that long ago with my non-cat, the splits didn't burn worth shitsky. Sounds to me like your wood ain't ready yet.
 

Jacklumber

Member
Oct 7, 2017
29
California
I haven't split the wood (Almond) before testing, I just did a surface test which read 20%. I'll get that done and let you know what reading is after splitting.
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,548
South Puget Sound, WA
Wood needs to be tested for the moisture inside. If it is reading 20% outside then the odds are it's still damp inside. Partially seasoned wood coals up a lot.
 

pjwlk

New Member
Dec 31, 2018
3
Ontario Canada
Hi all. I'm new to the forum as well as wood burning. I'm looking for a solution to a similar problem. I'm currently trying the move the coals to the front and load wood east-west at back solution mentioned above. My stove (Regency F2400 Classic) doesn't seem to do a great job burning east-west for some reason. I've tried loading east-west a couple of times for an over-night burn but the back pieces don't light or go out easily and the fire dies early. The wood for this test has been in my shed for about 3-4 years so I'm guessing it's dry enough.

Anyhow, I'm having to empty my ash (with coals) about every 3 days at most. Otherwise it gets tough to get new wood into the stove. My low seasoned wood condition is unfortunately requiring me to mix in some un-seasoned wood (I bought 2.5 bush cords and yeah sham on me for not asking if it was seasoned...) I'm guessing that the un-seasoned wood is going to be an issue that would leave ice-cubed sized coals

I've heard a number of people boast about their stoves producing a fine powder ash, and many others stating that they only empty ash every week or two. So I'm wondering, how often do you empty your ash and what does it look like?
 

saydinli

Burning Hunk
Nov 6, 2016
248
Near Fergus Ontario
How much ash has alot to do with the type of wood and the temperature of combustion of the wood.


Sent from my iPhone using Tapatalk
 

begreen

Mooderator
Staff member
Nov 18, 2005
89,548
South Puget Sound, WA
Try putting a couple shorter, 2" thick splits N/S about 5" apart under the E/W splits. That will allow air to get underneath the big splits for a quicker start and more even burn in the rear. That will help, but poorly seasoned wood is a pain regardless. Mixing it with some dry 2x4 cutoffs, or compressed sawdust bricks will help a bit.
 

pjwlk

New Member
Dec 31, 2018
3
Ontario Canada
Thank you for your responses. I'll tried the N-S pieces under the E-W and yes that made a difference. I'm a lessee in a Nature Reserve area with about 100+ other folks who are all burning the same wood (mostly Maple & Beech) which comes from the reserve's forest. I can't tell the internal combustion temperature of my stove but I try to keep the flue temperature of my double wall pipe at ~600F. My probe type thermometer (SBi) shows a optimum flue temp range of 400F-900F. Perhaps keeping the flue temp at 600F is simply too low. Maybe I should try for ~700F. Our place gets smoking hot if we go above that though.

I was just over at a friends site earlier today and his ash is mostly powder with some small pieces of coal where mine is mostly coals with some ash. His stove is similar in size but older.

Thanks again for your advice.
 

Jacklumber

Member
Oct 7, 2017
29
California
I did a moisture test after splitting the almond and it was ranging 20~22°C, but I do think my meter maybe faulty. The first time I used it I pushed one of the prongs into the casing. It gives a consistent reading but having one short and one long prong isn't ideal. Also I think my burning methods don't help. I have chord of oak coming next week so will try that in combination with North/South method explained by begreen. GreenStart makes one lazy, it fires up even the worst of loading methods into a blaze.
 

pjwlk

New Member
Dec 31, 2018
3
Ontario Canada
I did some trials. Temperatures around 700° F are burning the coals down a lot more. We're balancing the extra heat out by opening windows/vents, Thanks again guys.